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A promotional recording, or promo, is an audio or video recording distributed free, usually in order to promote a recording that is or soon will be commercially available. Promos are normally sent directly to broadcasters, such as
Promos are often distributed in plain packaging, without the text or artwork that appears on the commercial version. Typically a promo is marked with some variation of the following text: "Licensed for promotional use only. Sale is prohibited." It may also state that the promo is still the property of the distributor and is to be "returned upon demand." However, it is not illegal to sell promotional recordings,  and recalls of promos are extremely rare and unenforced. 
Because promos are produced in smaller quantity than releases made available to the general public, they are sometimes considered valuable collectors' items. They are never intended for sale in record stores.
This article needs to be updated.(May 2015)
A promo single (short for promotional single) is a single that is made available to
The promo single is usually recognized by its limited liner notes and cover artwork as well as its unique catalog number (or the occasional lack thereof). Quite often,
There may also be promotion-specific terms stamped on the disc or its cover, most notably "For Promotional Use Only."
The advance promo single is furnished to DJs sometimes weeks or months in advance of a domestic release to give record labels an opportunity to build interest in the single and gauge response to the single. Unlike a finished promo single, these are commonly test pressings or